Variable selective automatic choke for shotguns



March 18, 1952 w. H. SEDBERRY 2,539,738

VARIABLE SELECTIVE AUTOMATIC CHOKE FOR SHOTGUNS Filed Jan. 13, 1950 4Sheets-Sheet 1 FIG. I.

a2 I A INIHWIMH 6 63 INVENTOR. W/L LIAM H. SEDBERRY March 18, 1952 w. H.SEDBERRY 7 2,539,733

VARIABLE SELECTIVE AUTOMATIC CHOKE FOR SHOTGUNS Filed Jan. 13, 1950 4Sheets-Sheet 2 32 52 47 e2 63 a/ as INVENTORQ- WILLIAM H. SEDBERRY March18, 1952 w. H. SEDBERRY 2,589,738

VARIABLE SELECTIVE AUTOMATIC CHOKE FOR SHOTGUNS Filed Jan. 13, 1950 4Sheets-Sheet :5

F1015. FIG. 15. FIG. 12*

FlG.22. A

INVENTOR. WILL/AM HVSEDBERRY ATTORNEYS March 18, 1952 W. H. SEDBERRY I2,589,738

VARIABLE SELECTIVE AUTOMATIC .CHOKE FOR SHOTGUNS Filed Jan. 13, 1950 '4Sheets-Shet 4 cum-1.1m

INVENTOR. WILLIAM H. SEDBERRX Mia/x4202 A T TORNEYS Patented Mar. 18,1952 UNITED STATES PATENT OFFICE VARIABLE SELECTIVE AUTOMATIC CHOKE FORSHOTGUNSH William H. S'edberry, Thompsons Station, Tenn.

Application January 13, 1950, Serial No. 138,416

7 Claims.

This invention relates to variable choke devices for shotguns, and moreparticularly to an adjustablechoke device for shotguns of the typewherein the device may be set to provide a cylinder choke for the firstshot and wherein the device is automatically adjusted for a greaterdegree of choke for the next shot. f

A main object of the invention is to provide a novel and improvedadjustable choke device for shotguns, said device being very simple inconstruction, being easy to mount on a shotgun, and providing a numberof degrees of choking action which may be readily selected as desired.

A..further object of the invention is to provide an improved chokedevice of the type wherein the device may be set to provide non-chokingaction for the first shot and to automatically shift to a chokingposition for the second shot, said device being inexpensive tomanufacture, invlv-' ing only a few parts, and being readily applicableto a conventional gun barrel.

.A still further object of the invention is to provide an improved chokedevice for shotguns of the type which may be set to shoot a certainpattern for the first shot and then a relatively choked pattern for thenext shot, said relatively choked patternrbeing automatically obtainedby the action of the device, the device being further arranged so thatthe device will reset to provide a relatively unchoked pattern for thethird shot, or. if sodesired, may be set to provide a choked pattern forall shots after the first shot.

A still further object of the invention is to provide' an improvedadjustable choke device for shotguns which may be set to shootcontinuously any one of four difierent patterns or which may be set toprovide a relatively unchoked pattern for the first shot and a modified,relatively choked pattern for the second shot, the choke device beingautomatically reset alternately after each shot to provide a differentpattern. 7

I A still further object of the invention is to provide an improvedvariable selective automatic chokedevice for shotguns having meanswhereby the barrel of a gun can have its outer part adjusted from acondition providing a cylinder pattern to a condition providing amodified choke pattern, or from a modified choke position to a fullchoke condition, the device functioning to.

change over from one condition to another automatically, said devicebeing further provided with means so that it may be made non-automaticand maybe'set to provide continuously anyone of four patterns. 4

A still further, object of the invention is ,55

vide a choke reforming attachment for a shotgun for unchoking or openinga shot pattern to provide improved control of the shot column, saidreforming device being very simple in construction, being easy toinstall, being readily adjustable to provide different degrees of shotpattern reformation, and being very inexpensive to manuiacture.

Further objects and advantages of the invention will become apparentfrom the following description and claims, and from the accompanyingdrawings, wherein:

Figure 1 is a side elevational view of an improved automatic chokedevice constructed according to the present invention shown mounted on ashotgun of the pump gun type;

Figure 2 is an enlarged elevational view of the Figure 4 is an endelevational view of the muzzle end of the gun barrel of Figure 3;

Figure 5 is a side elevational view, partly broken away, of the outerretaining sleeve member of the automatic choke device;

Figure 6 is an end elevational view of the sleeve device of Figure 5;

Figure 7 is a'fragmentary, enlarged, longitudinal, cross-sectional Viewtaken through the muzzle portion of the barrel of the gun of Figure 1,said-view being taken on line. 1-1 of Figure 8:

Figure 8 is an end elevational view of the muzzle of the gun barrel,showing the choke device set to provide a cylinder pattern;

Figure 9 is a view similar to Figure 8, but showing the device set toprovide a choke pattern; Figure 10 is an enlarged, perspective view ofthe end of the barrel of the gun of Figures 1 and 2;

Figure 11 is a fragmentary, enlarged, perspec- Figure 13 is an enlarged,cross-sectional, detail view taken on line l3.l-3 of Figure 2;

and the forward portion thereof curving in-- wardly, as shown in Figures2 and 23. The vanes are arranged so that the gases discharging from theslots 62' apply a clockwise torque shortly after the firing of a shot onthe sleeve member 41, as viewed in Figure 8, when they reach theinwardly curved forward ends of the vanes.

As shown in Figures 5 and 6, the interior wall of the sleeve member isformed with longitudinal grooves 64'conforming in shape with the ribs 35of the barrel fingers 34, the grooves 64 defining therebetweenlongitudinal ribs 65-similar in shape to said ribs'35. When the sleevemember 41 is arranged with the ribs 65 received between the respectiveadjacent ribs 35 of the barrel fingers, saidfingers are in a relativelyspread position, as shown in Figure 8. When the sleeve member 41rotatesclockwise, as viewed in Figure 8, for example, as a result of ashot being fired, the ribs 65 ride up the camming surfaces 36 onto theribs 35 and flex the fingers 34 inwardly to the positions shown inFigure 9. This provides a choking action at the gun muzzle for the nextshot. The next shot .will again cause the dis charging gases to exert aclockwise torque on sleeve member 41 at the vanes 63. This torque willagain produce clockwise rotation of the sleeve member, moving the ribs65 into positions between successive ribs 35, thereby releasing thefingers 34 and allowing said fingers to spread to the positions ofFigure 8, whereby the gun muzv zle is unchoked for the next shot.

The minimum degree of choking. efiect is obtained when the sleeve member41 is arranged so that the stud 46 is located in the groove 50 and theribs, 65 are positioned between adjacent ribs 35, as in Figure 8. Amodified choking effect'i's obtained when the sleeve member .is rotatedto the position of Figure 9. A further modified choking effect isobtained when the sleeve mem-- ber 41 is arranged sorthat stud 46 islocated in the groove 49 with the ribs 65 positioned betweenadjacentribs 35, inasmuch as sleeve member 41 flexes the fingers 34inwardly when it is moved forwardly on the barrel to enga e stud 46 ingroove 49. Full choking effect is obtained when, with the stud 46 ingroove 49, the sleeve member is rotated to the position of Figure 9,whereby the fingers 34 are flexed inwardly to a maximum de r .m

The sleeve member 41 may be locked in any one of the fourabove-described positions, pro- Viding either no choking action,modified chok.-. ing action, further modified choking action, or fullchoking action, by engaging the-tip of the locking screw 56 in eitherrecess 39, 38, 4| or 40.

..The spring locking member 52 is yieldable to allow the sleeve member41 to be manually ad- J'usted on'th'e barrel 32. "'With the screw 56 ina retracted position, such adjustment may be therefore readily made.When the stud 46 is engaged'in groove 50,'the locking pins 55 engagethe-positioningrecesses 44 of the groove 42, andinsure-correct, relativerotational 'p'ositioniiig bfitl'ie c'amini ig ribs '65 and 35 duringeither manual "settingofthe sleeve'member or a'uto-' matic settingthereof, as a result of firing thegun. "Similarly, when the stud 46 isengaged in groove 49, the locking pins 55 engage in'the positioningrecesses 45 of groove 43.

As shown in Figure 2, the barrel 32 is provided with a longitudinalindex mark 66 and the sleeve member is provided with markings C and Mregistrable with the index mark 66 and indicating either a choke ora-modified adjustment of the sleeve member. 1

Secured to the barrel rearwardly adjacent the sleeve member 41 is aconventional sight 61.

Designated at 16 is a locking member formed with a tapered forward tip1| loosely-engageable;

in locking recesses 12 formed in the rear edge of the sleeve member 41,said locking recesses being spaced apart by the same angles as the ribs65. Member 16 is formed with a longitudinal slot 13 through which extendthe headed screws 14 and 15 holding the member 10 secured to the barrel.The distance betweenthe screws 14 and 15 is less than the length of theslot 13 by a value greater than the length of tip 1| so that the member10 may be moved rearwardly out of engagement with the rear edge of thesleevemember 41, as shown in Figure 11. The slot 13 is form-ed with aright-angled branch 16 spaced from the rear end of the slot by the samedistance as the spacing between screws 14 and 15. the arrangement beingsuch that when the tip I is engaged in a recess 12, the screw 14 is inthe rearend of the slot 13 and the member 10 may ro tatecounterclockwise, as viewed in Figure 12, responsive to the movementofthe sleeve member 41 from its initial non-choking position to achoking position after the first shot. Figure 12 shows the sleevemember41 moved to said choking position. It will be seen from Figure 12 thatthe member 10 has: been rotated to engage screw 15in the right-angledbranch 16 and that the member 16 is held against furthercounterclockwise rotation. Therefore, with the member 10 arranged as inFigure 12, the second shot and all subsequent shots will be choked,since the sleeve member 41 is held against further rotation by thelooking tip 1| of the member 10.

The member 16 maybe placed in an inoperawasher which causes member 10'toremain in a given position of adjustment thereof and yet al-'- lo'wsmember to bel'moved by thumb pressure;- From the foregoing description,it will beam parent that the sleeveme mber 41 may be set bymeans of thelocking screw 56 to provide any one of four different constant shortpatterns. With the locking screw 56 disengaged from the barrel 32, thesleeve member .41 may be set either in a first position, wherein stud 46is located in groove 56 to automatically provide a cylinder pattern onthe first shot, a modified choke pattern on the second. shot, andalternating cylinder and modified choke patterns on successive shots.With the stud 46 located'i'n groove 49, the sleeve mem ber automaticallyprovides a modified'choke pattern on the first shot, a full chokepattern on the second'shot, and alternating modified choke and fullchoke patterns on successive shots. the stud 46 located in groove 56,the locking member 16 may be set. to provide acylinder pat-i tern on thefirst shot and constant modified choketpatternsron all successiveshots.-

The structure above described may be manu- With fea re p atel an a d. beh a d onto the barrel of aconventional gun instead of being made unitarywith the gun barrel; within themuzzle end ofaconventional shotgunbarreland I8 designatesthe cross-sectional appearance of; the normal shotpattern obtained therefrom. It will be seen that the normal; shotpattern contains numerous open areas, 19' and shows'nu merous randomshots around the circumference of the: pattern, indicating poor control.of the directivity of the shot. This effect may be corrected-by the useof a shot reforming sleeye, such as shown at 80 inFigures 18 andl9. Thesleeve 80 slips over the muzzle end l1 and may besecured on said;muzzleend in anyone of three different positions. The sight bolt,shownat 8 l. is employed in the manner shown in Figures 19 and 20,together with additional securing screws 82, 82 to fasten the reformingsleeve 80 to the muzzleencl. v

Reforming sleeve 80 is formed with one or more circumferential rows ofgas its front rim as shown at 8 d. When the sleeve 80 is set to providea full reforming effect, as

shown in Figures 18 and 19, the propelling gases.

flow past the-shot propelling wad 85 as said wad leaves themuzzle endandthegases flow partially through openings 83, meanwhile providing, a

gathering effect on the shot which establishes a more homogeneouscylinder pattern, shown at minimum reforming effect and substantiallythe v normal scattered cylinder pattern 18 is obtained.

As shown inFigures 27 and 28, the, patternifeforming sleeve may beformed with opposing, longitudinal slots 88 haying notches. 89, 90 andSI. The sleeve of Figures 27 and 28 maybe secured on the muzzle end of'ashotgunbarreli by suitable securing screws engaged through the slots 88,the desiredposition of adjustment, of'the sleeve being established bysetting the sleeve so that the securing screws are located. either inthe notches 9|, 99 or 89, providing full' refor"m ing effect,modified'reforming effect or minimum reforming effect, respectively. Asshown in Figure 28. the sight bolt 8! may be, employed'as one of thesecuring screws.

Referring now to Figures 23 and 24, 9 2 desig nates a pattern reformingsleeve similar inconstruction to the sleeve 80 of'Figures 1i} and 19;but provided with internal screw threads at its rear end which areengageable with the external screw threads 6lof thechoke sleeve 41. The

pattern reforming sleeve 92' is mountedon=the discharge openings 83 atits forward portion and is rounded off at By. setting sleeve sleeve 41;is. set; for. full chokelefiect. w thoutusins:

the; choke; reforming sleeve, 92;. Designated at: 91; isoneof themodified-choke patterns obtained.- by the use ofsleeve; 41,. again;without using;

the; r fo min sleeve. 92,-. Desi nated at; 98 s: thecy 'nderpatternobtained when; the sleeve 41- is; set; in; nqnrchoking position.Designated; at: 9&1 is a pattern obtained when, the reforming;

sleeve; a2: is employed. with; thepsleeye ll, the} sleeve; 41 being;set; in, maximum, choking po';-. sitiq r- Des nated at: Inn: is.patternzobta when the; reforming: sleeve 92," isv employed; on.

sleev 41;. e v 41 bein set. to; amodifi'ed: choke; p siti t. Desi natedat; I01 is a.nove1,. very-:wide; shot pattern; obtainedwhenthegreforming sleeve. 92 is employedon sleeve; 41; withqsleeve. 41setizin urhok position. The: wide'pattern l.0l is; very' desirable for;shooting. in, dense cover. where, game must be ;s hot at;a,very. close.distanca. Frornthe foregoing, it will;be apparentsthat. the; patternreforming sleeyewill provide, several additional shot patterns beyondthosegobtainable. frornflhe. use of; the; automatic choke: device.

While certai specific embodiments .of a..vari.-. ableselective automaticchoke device and pattern reforming; means for a shotgun have; been disclosed inthe foregoing description, it; willcbe.

understood that various modifications withinvv the end thereof provided,with, av plurality. of' spaced slots extending; longitudinallyinwardly-from said muzzle: end-and, completely through the barrel, the,portions ofthe barrel'intermediate adjacent slots forming longitudinalspaced resilient fin-. gers, arib; on the exterior faceof eachfingerpositioned adjacent one side edge thereof and spaced from theothersideedge thereof and extending-longitudinally of said finger, therebeinga plurality. of spaced apertures in said barrel arranged"longitudinally thereof and inwardly-of said fingers; a sleevepositionedon said barrel inwardlyof said slots and mountedon said barrelforsliding axial and rotational movement, said sleeve having a pluralityof apertures arranged in= spaced relation: thereabout intermediate its:

ends, the apertures in said-sleeve being in registry with'theaperturesin said barreL'anda plurality;

of spaced ribs on the-interior face of said sleeve;

extending longitudinally of and inwardly fromone end of said sleeve,each rib on said sleeye being interposed between; a rib on one fingerand a rib: on the next adjacent finger and,,engageable-with'theribonsaid'one finger uponroe tative movement of said sleeve to flex thefingers toward each other.

2. In a shotgun, a barrelhaving the muzzle end thereof-provided with aplurality of spaced slots extending longitudinally inwardly from saidmuzzle end and completely through the barrel; the portions of the barrelintermediate adjacent;

slots forming longitudinal spaced resilient fingers, arib on theexterior face of each; finger. positioned adjacent one side ed ethereof-and spaced from the other side edgethereofandjrextendinglongitudinally; of said fingers, a studprof- .iecting exteriorly of saidbarrel, and spaced:-.in,-. wardlyi ofsaid slots, there being a,plurality: of. spaced ap r u s n sa d arre arran ed; lensitudinallythereof'and inwardly. of; said fingersa sleeve positioned on said barrelinwardly of saidgageable with said stud for guiding said sleeve in itssliding axial movement and holding said sleeve against rotationalmovement, said sleeve having a plurality of apertures arranged inspacedrelation thereabout intermediate its ends, the apertures insaidsleeve being in registry with the apertures o I in said barrel, and aplurality of spaced ribs on the interior face of said sleeve extendinglongitudinally of and inwardly from one end of said sleeve, each rib onsaidsleeve being interposed between a rib on one. finger and'a rib onthe next adjacent finger and engageable with the rib on said: one fingerupon rotative movement of said sleeve to fiex the fingers toward eachother.

; -3. In a shotgun, a barrel having the muzzle end thereof provided witha plurality of spaced slots extending longitudinally inwardly from saidmuzzle end and completely through the barrel, the portions of the barrelintermediate adjacent slots forming longitudinal spaced resilientfingers, a rib on the exterior face of each finger positioned adjacentone side edge thereof and spaced from the other side "edge thereof andextending longitudinally of said fingers, a stud projecting exteriorlyof said barrel and spaced inwardly of said slots, there being aplurality of spaced ape'r tures in said barrel arranged longitudinally.thereof and inwardly of said fingers, a sleeve positioned on said barrelinwardly'of said slots and mounted on said barrel for sliding axial androta-= tional movement, means on the inner face of said sleeve andslidably engageable with said stud for guiding the sleeve in itsrotational movement and holding the sleeve against sliding axialmovement, a second means on the inner face of said sleeve adjacent toand in communication with said first means and slidably engageable withsaid stud for guiding said sleeve in its sliding axial movement andholding said sleeve against rotational movement, a resilient yoke fixedon saidsleeve intermediate its ends, detent means carried by said yokeextending through said sleeve and interengaging with a holding means onthe inner face of said barrel for securing said sleeve in a selectedposition of its rotational movement, said sleeve having a plurality ofapertures arranged in spaced relation thereabout intermediate its ends,the apertures in said sleeve being in registry with the apertures insaid barrel, and

a plurality of spaced ribs on the interior face of said sleeve extendinglongitudinally of and inwardly from one end of said sleeve, each rib onsaid sleeve being interposed between a rib on one finger and a rib onthe next adjacent finger and engageable with the rib on said one fingerupon rotative movement of said sleeve to flex the fingers toward eachother.

4. In a shotgun, a barrel having the muzzle end thereof provided with aplurality of spaced slots extending longitudinally inwardly from saidmuzzle end and completely through the barrel, the portions of the barrelintermediate adjaprojecting exteriorly of said barrel and spacedinwardly of said slots, there being a plurality of spaced apertures insaid barrel arranged .longiitudinally thereof and inwardly of saidfingers, a

sleeve positioned on said barrel inwardly of said slotsand mounted onsaid barrel for sliding axial and rotational movement, means embodyingat least a pair of spaced annular grooves (in the inner face of saidsleeve and slidably engageable with said stud for guiding the sleeve inits reta ltional movement and holding the sleeve against sliding axialmovement, a second means embody ing a longitudinal groove on the innerface of said sleeve and intersecting said pair of annular grooves andslidably engageable with said stud for guiding said sleeve in itssliding axial move.-

' 'iiient and-holding said sleeve against rotational movement, saidsleeve having a plurality of aper-. tures arranged in spaced relationthereabout in.- termediate its ends, the apertures in said sleeve beingin registry with the apertures in said bar;- rel, and a plurality ofspaced ribs on the in: terior face of, said sleeve extendinglongitudinally of and inwardly from one end of said sleeve, each rib onsaid sleeve being interposed between a rib on one finger and a rib onthe next adjacent finger and engageable with the rib on saidone fingerupon rotative movement of said sleeve to flex the fingers toward eachother.

- 5. In a shotgun, a barrel having the muzzle end thereof provided witha plurality of space'd slots extending longitudinally inwardly from saidmuzzle end and completely through the barrel, the portions of the barrelintermediate adjacent slots forming longitudinal spaced resilientfingers, arm on the exterior face of each finger positioned adjacent oneside edge thereof and spaced from the other side edge thereof andextending lon gitudinally of said fingers, a stud projecting exteriorlyof said barrel and spaced inwardly of said slots, there being aplurality of spaced apertures in said barrel arranged longitudinallythereof and inwardly of said fingers, a sleeve positioned on said barrelinwardly of said slots and mounted on said barrel for sliding axial androtational movement, means embodying at least a pair of spaced annulargrooves on the inner face of said sleeve and slidably engageable withsaid stud for guiding the sleeve in its rotational movement and holdingthe sleeve against sliding axial movement, a second means embodying alongitudinal groove on the inner face of said sleeve and intersectingsaid pair of annular grooves and slidably engageable with said stud forguiding said stud for guiding said sleeve in its sliding axial movementand holding said sleeve against rotational movement, said sleeve havinga plurality of apertures arranged in spaced relation thereaboutintermediate its ends, the apertures in said sleeve being in registrywith the apertures in said barrel, a plurality of spaced ribs on theinterior face of said sleeve extending longitudinally of and inwardlyfrom one end of said sleeve, each rib on said sleeve being interposedbetween a rib on one finger and a rib on the next adjacent finger andengageable with the rib on said one finger upon rotative movement ofsaid sleeve to flex the fingers toward each other, and a plucent slotsforming longitudinal spaced resilient '1 fingers, a rib on the exteriorface of each finger positioned adjacent one side edge thereof and spacedfromthe other side edge thereof and ex-' tending longitudinally of saidfingers, a stud rality of spaced vanes extending longitudinally inwardlyfrom said one end of said sleeve and en'di thereof provided with aplurality of spaced slots extending longitudinally inwardly from saidmuzzle lend completely through the barrel, the

portions of the barrel intermediate adjacent slots itudinally of saidfingers, there being a plurality of spaced apertures in said barreliarranged 1ongitudinally thereof and inwardlyof said fingers, a sleevepositioned on said barrel inwardly of said slots and mounted on saidbarrel for sliding axial and rotational movement, said sleeve having aplurality of apertures arranged in spaced rela- "tion ithereaboutintermediate its ends, the apertures in said sleeve being in :registrywith the apertures in said barrel, a plurality of spaced .ribs on theinterior face of said sleeve extending longitudinally of and inwardlyfrom one end of said sleeve, each rib on said sleeve being interposedbetween a rib on one ,fingerand a rib on the next adjacent finger andengageable with the rib on said one finger upon rotative movement ofsaid sleeve to flex the fingers toward each other, and a locking elementcarried by said sleeve and selectively engageable with one of aplurality of spaced receiving means formed in said barrel to lock saidsleeve in a selected position on said barrel. v

7. In a shotgun, a barrel having the muzzle end thereof provided with aplurality of spaced slots extending longitudinally inwardly from saidmuzzle end and completely through the barrel, the portions of the barrelintermediate adjacent slots'forming longitudinal spaced-resilientfingers, a rib on the exterior face of each finger positioned adjacentone side edge thereof and spaced ,from the other side edge thereof andextending longitudinally or said fingers, there being a ,plurality ofspaced-apertures vin said barrel arranged longitudinally thereof andinwardly ofsaid :gers, thesleeve positioned on said barrel inwardly ofsaid .slotsand mounted on said barrel tor slidingaxial and rotationalmovement, :a resilient yoke fixed on said sleeve intermediate its ends.detent means carried by said yoke extendin through said sleeve andinterengaging .with adiacent recesses of a plurality of spacedrecessesarranged about and :formed in each of a pair of longitudinally spacedannular grooves formed on the inner face of said barrel forsecuring'isaid sleeve in a selected position .of its rotationalmovement, said sleeve having a plurality of apertures arranged in spacedrelation thereaboutintermediate its ends, the apertures {in .said sleevebeing in registry with the apertures 'insaidibare rel, and a pluralityof spaced ribs on the interior face of said sleeve extendinglongitudinally of and inwardly from one end of said .sleeve, each rib onsaid sleeve being interposed between-ail on one finger and a rib onthenext'adjacent rim ger and engageable with a rib onxsaidone'iingerupon rotative movement of said sleeve to .flex the fingers toward eachother.

WILLIAM HCSEDBERRY.

KEFERENCES CITED The following references are of record in the file ofthis patent:

